Adjustable drainage foil for paper machines



July 7, 1964 L. TRUXA ADJUSTABLE DRAINAGE FOIL FOR PAPER MACHINES Filed Nov. 29, 1962 I l l ummmmm INVENTOR. Es LIE TE UXA ATTOFNE).

United States Patent 3,140,225 ADJUSTABLE DRAINAGE FOIL FOR PAPER MACHINES Leslie Truxa, Montreal, Quebec, Canada, assignor to Dominion Engineering Works, Limited Filed Nov. 29, 1962, Ser. No. 240,941 9 Claims. (Cl. 162352) This invention relates to Fourdrinier type paper machines and more particularly to drainage foils, as used in Fourdriniers.

This invention is an improvement over that contained in application number 134,875, filed August 30, 1961, now abandoned.

As was pointed out in this earlier case, in Fourdrinier type paper machines an aqueous suspension of fibres, called stock, is discharged through an orifice, known as a slice, onto a moving endless wire or non-metallic sceen. The moving screen passes around a roll known as the breast roll and leaves the breast roll in a substantially horizontal direction. The stock issuing from the slice is deposited on the moving screen close to its tangency with the breast roll. After leaving the breast roll the screen passes over one or more forming boards; next, the screen passes over a plurality of table rolls, whose function is to accelerate drainage of water from the stock on the screen; on leaving the last of the table rolls the screen passes over a number of suction boxes which are piped up to a vacuum pump after which the screen passes over the suction couch roll and is led back to the breast roll again by way of various rolls having functions such as driving, tensioning and guiding the screen.

About ninety-eight per cent of the water originally contained in the stock is removed by the Fourdrinier screen so that the aqueous suspension of fibres is converted, during its residence on the screen, into a continuous web of paper.

Many disadvantages associated with conventional Fourdrinier type paper machines are overcome in the device of Canadian Patent No. 586,544, in which a plurality of stationary drainage members, or foils, is substituted for one or more of the table rolls. This results in Fourdrinier sections of shorter length and eliminates many of the disadvantages associated with table rolls.

The present invention relates to a means of varying the drainage capacity of drainage foils, as disclosed in said Canadian Patent No. 586,544.

The general object of the invention is to provide a new and improved device for changing the drainage capacity of a drainage foil by varying the angle of the foil trailing surface with respect to the Fourdrinier wire, which device is an improvement over that contained in my application number 134,875, filed August 30, 1961.

The principal object of this invention is to provide a new and improved device of the type described which is significantly less expensive to manufacture than any disclosed up to this time.

Another object of the invention is to be able to perform the general object with the machine in operation. In this way, the result of such adjustment can be easily observed.

Another object is to provide a device which can be easily mounted on conventional Fourdrinier support beams, to facilitate conversion of existing equipment for use with drainage foils.

Another object of the invention is to provide an adjustable drainage foil with easily replaceable Wear elements.

Other objects and advantages of the invention will be apparent from the foregoing description taken in connection with the accompanying drawings in which the 3,149,225 Patented July 7, 1964 ice preferred forms of the invention have been given by way of illustration only.

Referring to the drawings:

FIG. 1 is a partially sectioned side view of the invention; and

FIG. 2 is a sectional view through line 2-2 of FIG. 1 showing details of one execution of the invention.

Referring more particularly to the drawings wherein similar reference characters designate corresponding parts throughout the several views, the drainage foil shown embodying the invention comprises a body 10 having a foil leading portion 11 effectively integral therewith, and a plurality of spaced brackets 12 spot welded to the inner portion 13 of body 10 and the upper surface 14 of the base portion 15 of body 10.

Brackets 12 are provided with aligned openings 16 adapted to contain the slidably fitted adjusting bar 17. Projection members 18 are carried by adjusting bar 17. Each projection member 18 is positioned in a cam slot 19, one of which is provided for each projecting member 18.

Cam slots 19 are formed in cam portion 20a of angle structure 20 which also incorporates foil trailing portion 20b.

A flexible spring steel impervious member 21 is spot welded to the upper surface 22 of foil trailing portion 20b of angle structure 20 and the upper surface 23 of the foil portion 11 of the body 10. A non-metallic covering 24 is positioned on flexible impervious member 21.

The drainage foil thus composed is held in operative position upon the paper machine by means of a bolt or similar fastener 25 extending downwardly through an opening 26 is the base 15 of the body 10.

Adjustment of the foil is easily accomplished by means of the adjusting nut 26 located upon the threaded extension 27 of the adjusting bar 17, the degree to which such is adjusted being readily readable from the position indicator 28, likewise an extension of adjusting bar 17 The main object of this invention is to obtain approximately 4 degrees angular adjustment of the covering 24. It will be seen that when adjusting nut 26 is rotated upon the threaded extension 27 of the adjusting bar 17, such threaded extension 27 will move axially and, there fore, adjusting bar 17 will move in openings 16.

Thus, the projection members 18 will move within the cam slots 19 in the cam portion 20a of angle structure 20. It will be seen that, due to the angular disposition of cam slots 19 within cam portion 20a or angle structure 20 such movement of the projection members 18 in slots 19 will cause the foil trailing portion 20b of angle structure 20 and, hence, the impervious member 21 and covering 24, to attain differing angles.

It is pointed out that, if desired, the projections or projection members 18 may be carried by the angle structure 20 and the cam slots 19 provided in adjusting bar 17.

One of the advantages of being able to vary the angle of relief of the drainage foil, whilst the machine is in operation, is that the paper machine operator can vary the drainage rate of the Fourdrinier table and so obtain optimum paper quality.

Another advantage is that the drainage foil assemblies can be easily replaced, thereby allowing Fourdrinier wires of different materials to be interchanged, without the need for long periods with the paper machine non-operational.

From the foregoing it will be seen that I have provided new and improved means for obtaining all of the objects and advantages of the invention.

I claim:

1. In a device of the character described having a body having a foil leading portion and a foil trailing portion,

an adjusting bar carried by said body, projections and cam elements on said adjusting bar and said foil trailing portion, said cam elements operatively engaging said projections whereby said trailing portion may be angularly adjusted relative to said leading portion, the improvement comprising, said foil leading portion and said foil trailing portion being formed separate from each other, and a separate flexible impervious member connecting said separate foil leading and trailing portions.

2. In a device of the character described having a body having a foil leading portion and a foil trailing portion, an adjusting bar carried by said body, projections and cam elements on said adjusting bar and said foil trailing portion, said cam elements operatively engaging said projections whereby said trailing portion may be angularly adjusted relative to said leading portion, the improvement comprising, said foil leading portion and said foil trailing portion being formed separate from each other, and a separate flexible impervious member connected to said foil leading and trailing portions adjacent the upper surfaces thereof.

3. In a device of the character described having a body having a foil leading portion and a foil trailing portion, an adjusting bar carried by said body, projections and cam elements on said adjusting bar and said foil trailing portion, said cam elements operatively engaging said projections whereby said trailing portion may be angularly adjusted relative to said leading portion, the improvement comprising, said foil leading portion and said foil trailing portion being formed separate from each other, and a separate flexible impervious member connected to and overlying said foil leading and trailing portions.

4. In a device of the character described having a body having a foil leading portion and a foil trailing portion, a slidably fitted adjusting bar carried by said body, projections on said adjusting bar, cam elements formed on said foil trailing portion, said cam elements operatively engaging said projections whereby said trailing portion may be angularly adjusted relative to said leading portion, the improvement comprising, said foil leading portion and said foil trailing portion being formed separate from each other, and a separate flexible impervious member connecting said separate foil leading and trailing portions.

5. In a device of the character described having a body having a foil leading portion and a foil trailing portion, an adjusting bar carried by said body, projections and cam elements on said adjusting bar and said foil trailing portion, said cam elements operatively engaging said projections whereby said trailing portion may be angularly adjusted relative to said leading portion, the improvement comprising, said foil leading portion and said foil trailing portion being formed separate from each other, and a separate flexible impervious member connecting said separate foil leading and trailing portions and said flexible impervious member having a nonmetallic covering.

6. In a device of the character described having a body having a foil leading portion and a foil trailing portion, an adjusting bar carried by said body, projections and cam elements on said adjusting bar and said foil trailing portion, said cam elements operatively engaging said projections whereby said trailing portion may be angularly adjusted relative to said leading portion, the improvement comprising, said foil leading portion and said foil trailing portion being formed separate from each other, and a separate flexible impervious member connected to and overlying said foil leading and trailing portions and said flexible impervious member having a non-metallic covering.

7. In a device of the character described having a body having a foil leading portion and a foil trailing portion, an adjusting bar carried by said body, projections and cam elements on said adjusting bar and said foil trailing portion, said cam elements operatively engaging said projections whereby said trailing portion may be angularly adjusted relative to said leading portion, the improvement comprising, said foil leading portion and said foil trailing portion being formed separate from each other, and a separate flexible impervious member connecting said separate foil leading and trailing portions, and spaced supports secured to said body for supporting said adjusting bar.

8. In a device of the character described having a body having a foil leading portion and a foil trailing portion, an adjusting bar carried by said body, projections and cam elements on said adjusting bar and said foil trailing portion, said cam elements operatively engaging said projections whereby said trailing portion may be angularly adjusted relative to said leading portion, the improvement comprising, said foil leading portion and said foil trailing portion being formed separate from each other, and a separate flexible impervious member connecting said separate foil leading and trailing portions and said flexible impervious member having a non-metallic covering, and spaced supports secured to said body for supporting said adjusting bar.

9. In a device of the character described having a body having a foil leading portion and a foil trailing portion, an adjusting bar carried by said body, projections and cam elements on said adjusting bar and said foil trailing portion, said cam elements operatively engaging said projections whereby said trailing portion may be angularly adjusted relative to said leading portion, the improvement comprising, said foil leading portion and said foil trailing portion being formed separate from each other, and a separate flexible impervious member connected to and overlying said foil leading and trailing portions and said flexible impervious member having a non-mettalic covering, and spaced supports secured to said body for supporting said adjusting bar.

References Cited in the file of this patent UNITED STATES PATENTS 1,189,588 Lander July 4, 1916 2,694,345 Hornbostel Nov. 16, 1954 2,928,465 Wrist Mar. 15, 1960 3,017,930 Dunlap Jan. 23, 1962 3,027,940 Dunlap Apr. 3, 1962 FOREIGN PATENTS 399,739 Great Britain Oct. 12, 1933 

1. IN A DEVICE OF THE CHARACTER DESCRIBED HAVING A BODY HAVING A FOIL LEADING PORTION AND A FOIL TRAILING PORTION, AN ADJUSTING BAR CARRIED BY SAID BODY, PROJECTIONS AND CAM ELEMENTS ON SAID ADJUSTING BAR AND SAID FOIL TRAILING PORTION, SAID CAN ELEMENTS OPERATIVELY ENGAGING SAID PROJECTION WHEREBY SAID TRAILING PORTION MAY BE ANGULARLY ADJUSTED RELATIVE TO SAID LEADING PORTION, THE IMPROVEMENT COMPRISING, SAID FOIL LEADING PORTION AND SAID FOIL TRAILING PORTION BEING FORMED SEPARATE FROM EACH OTHER, AND A SEPARATE FLEXIBLE IMPERVIOUS MEMBER CONNECTING SAID SEPARATE FOIL LEADING TRAILING PORTIONS. 